Ultracold gases for quantum simulation of non-equilibrium systems

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In behaviour like superconductivity, where electricity flows with exactly zero loss, relationships between particles at different positions in the system, called "quantum correlations," provide system-wide communication that leads to many-body behaviour. Many-body cooperativity translates quantum effects (usually associated with microscopic particles) to a human scale, where they are accessible and exploitable. The probabilistic nature of quantum mechanics makes predicting these phenomena with calculations on conventional computers feasible only for simple models or small numbers of particles. "Quantum simulation" was proposed by Feynman as an alternative approach. Instead of relying on classical computers to model these behaviours, he reasoned, let quantum mechanics do the work. With real quantum particles whose interactions and environments are tailored to emulate many-body models, calculations are performed by allowing Nature to act according to the laws of quantum mechanics. Solutions are obtained via experimental measurement.**In this research program, we will use laser-cooled ultracold quantum gases as the medium for quantum simulation. At temperatures just billionths of a degree above absolute zero, random motion associated with temperature is all but eliminated, yielding both system-wide quantum correlations and unparalleled control over interactions and environments. These experiments will reveal the essential ingredients leading to a model's quantum many-body order, by examining questions about its energy, ground state, and dynamics. **The Ultracold Quantum Gases Laboratory will focus on many-body systems whose correlations arise as a result of "artificial gauge fields." In these environments, an internal property of the quantum particle, such as "spin," is intrinsically related to an external property, such as momentum. A familiar example of a gauge field is a magnetic field, where these relationships are spatially dependent. Along with engineering artificial magnetic fields, we will implement alternative spin-momentum correlations, some of which are thought to exhibit "topological order:" unique non-local order that is especially good at preserving quantum correlations in the presence of environmental disturbances. Focussing our attention on non-equilibrium properties will provide insight into the factors that control the growth, preservation, and demise of quantum correlations.**This research program makes important contributions to Canada's leadership in quantum technology. By identifying specific conditions under which quantum materials will exhibit robust long-range correlations, this research will provide valuable input to engineers designing new quantum materials and devices. By providing the theoretical physics research community with measurement-based results of quantum many-body models, this research will encourage the pursuit of novel many-body phenomena. In bridging the divide between theoretical conception and practical realization, the research will facilitate the development of next-generation quantum materials, such as those that provide efficient energy transmission with better superconducting materials, or those that offer an exponential increase in computational capacity with devices that process and store resilient quantum correlations. This laboratory will provide young scientists with the opportunity to gain new skills by developing and using precision laser systems, custom electronic controls, and ultrahigh vacuum systems. As they continue their careers, these highly qualified personnel will be able to offer the precision of atomic physics techniques to a variety of industries and research disciplines.